When Adam Mans was a student at Minnesota State University, Mankato, he caught the astronomy bug but wisely, it turns out, got a math bug too and earned a double major in the two subjects.

When the astronomy gig didn’t work out, Mans used his math skills to become an ­actuary, learning the science of present value calculations. That led to a career in the investment business.

Today, Mans is president of Marquette Asset Management, with $1.2 billion under management and administration.

Owned by the Pohlad family of Minnesota Twins fame, Marquette manages investment portfolios for families and individuals with a net worth of more than $2 million, including some of the diversified Pohlad wealth.

Mans sat down this month in Marquette’s downtown Minneapolis offices to talk about navigating wealth in a complicated and sometimes tumultuous financial world.

Q: Tell us about Marquette Asset Management.

A: Companies like ours are measured by assets under management. We have about $800 million of client assets. We also have about $400 million under our administration that we are not managing directly. We have 140 family relationships with multiple generations of a family as clients. The Pohlad family is a client but not as much as people think. We manage part of their portfolio but the vast majority of our clients are outside the family. We were established in 2005.

Q: What is your basic investment philosophy?

A: We are long-term investors and diversified investors. When you come to a firm like ours — we know our clients quite well — we put together a well-diversified portfolio that may include equities, cash and alternative investments such as real estate, commodities or precious metals.

Q: Do you have a return-on-investment goal?

A: We don’t. You can’t promise a specific return. We look at different asset classes and have long-term goals. One mistake both big and small investors make is to become too focused on the short term. At the end of the day it is foolhardy to make investments decision based on where the S&P 500 will be at the end of the year. Decisions should be made around what are your financial goals, your life goals. We are not into the individual stock-picking business. The time, energy and money spent on active management … doesn’t pay for itself. Ninety percent of performance depends on allocation. How much is in cash? How much is in bonds? We focus on making sure that clients get market returns in various asset classes. The academic research is clear: it’s nearly impossible to consistently “beat the market” after costs and fees. So, for the large-cap domestic portion of our clients’ portfolios, instead of spending time, energy, and money in an attempt to beat the S&P 500, we invest to ensure we actually get S&P 500 returns.

Q: How did the recession affect your clients?

A: To the extent that our clients had equity portfolios, they experienced the market turndown. But none were forced to sell at the worst time. Our focus is on the long term. We want to take emotion out of the decision process.

Q: What is the investor’s mind-set in 2013?

A: Technically, the recession is over. But people still can’t believe the market can be as high as it is — that can’t be real. A lot of investors are still on the sidelines invested in bond funds and money market funds, very conservative, and they missed the rally.

Q: Can small investors learn lessons from the way Marquette manages money for large investors?

A: At it’s most basic level it is very simple, but sticking to it is very difficult. Our best advice is to turn off the TV [for financial programs]. What every investor can do is remain focused on the long term and invest in ways to meet those goals. Fear and greed will derail those plans — 2008 is a laboratory exercise in that. Stay focused, stay diversified, rebalance if necessary.